10 Tank's fish and tanks

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10 Tanks

Fish Herder
Apr 11, 2022
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Hello. No advice on changing tank water today. I'm doing 50 percent water changes this week on 12 fish tanks that range in size from 45 gallons to 300 gallons. I manage a tank for a local government business and take care of some Koi for a local botanical gardens. They like to bring their Koi to my place over the Winter months because my 300 gallon is heated. I put them in with my Goldfish. My Goldfish are nearly as large as their Koi. The fish get along very well and Koi are interesting fish. I keep three gold and one yellow Koi.

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Hello. I think I'll hang out on this thread. Maybe I can talk water keeping with some others or whatever they're doing today. The other threads seem to be a bit testy sometimes for my liking. Anyway, water changes are going well, no spills. After taking care of so many tanks for so many years, there better not be any missteps. I try to get all my tanks done in three days. The time it takes to remove and replace roughly half the tank water is about 30 to 40 minutes per tank on average. Of course the larger tanks do take a bit longer. I don't need to clean the filters every week because with so much water being changed so often, the filters don't get real dirty.

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Well let's see. Today, as on most Wednesday and Saturday afternoons, I and my wife helps me take care of a 55 gallon tank for a government office in town. It's a local conservation office. A very nice place and they have a very nice fish tank placed in a hallway in an area that most of the employees move through. The office manager has made the tank her personal project and pays for all the equipment, food and maintenance out of her own pocket. Such a nice person and thoughtful too. So, rest assured no taxpayers money has been used. Just thought I'd add that disclaimer. The tank has Tiger Barbs, some Tetras, a Pleco named "Spot" and some small shark type fish. Very interesting and nicely done. It also has some Zebra Nerite snails, very attractive.

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Hello. Today is Thursday and I'm changing the water in a 55, 100 and 300 gallon tank. Lost a five year old feeder Goldfish this morning in the 100. It's funny, I set up a heavy plastic trough in my basement roughly five years ago and dropped about a dozen, small, feeder Goldfish in it. The fish cost about 26 cents a piece. They'll live anywhere from 5 to 7 years because they're raised in poor conditions and never develop much of an immune system. The other fish in the tank seem to be doing well and range in size from 4 to about 7 inches. At least they live in a healthy environment and didn't end their lives as lunch for some predatory fish.

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Okay, here goes. Today is Saturday and we're cleaning a 55 gallon tank for a local government office. It's something we do twice a week and we actually get paid for doing something we really enjoy. Go figure. Anyway, we remove and replace half the tank water and clean the filters. Actually, with such an aggressive water change routine, the filters are just taking in clean water and returning it to the tank. There are roughly 20 fairly small fish in the tank and they're egg layers. But, that's quite a few for 55 gallons of water. I've found if you keep the tank water a bit cooler, the fish will slow or stop their breeding. Which is a good thing if your tank is fully stocked. Cooler water holds onto oxygen better than warmer and the twice weekly water changes, keep the fish healthier. I think the office people overfeed the fish, but the more aggressive water change routine keeps the toxins out of the tank and the fish are doing very well.

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Here we go. Have a 300 gallon outdoor trough with four large Koi, and a dozen medium sized Goldfish and a dozen two to three inch fry. No filter, just a large bubbler that keeps the surface water moving. The water is heated and stays in the mid 50 degree range in the winter. In the warmer months, the water temperature is in the low 60s. I change half the water weekly or even a bit more often. The fish are fed some pellets every other day. Can't overfeed because of the number of fish and all the "business" they do. The Koi aren't mine. I keep them in the winter time for a local botanical garden that keeps the fish in a water feature during the Spring and Summer.

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Had an idea for a tank. Something fairly large, say 55 gallons. No filtration, just strong aeration. And, the secret, but really not so secret large and frequent water changes. I'm thinking I don't need any filtration if I just remove and replace most of the tank water every few days. More than half weekly, I'm thinking. Well, let's not just think about it, let's do it. Okay, done! This a a great hobby!

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Okay. Back on a more relevant topic here. I've maintained a tank for a local government business for the past few months and all is going well. Haven't needed to heat the tank because the temperature has stayed at a constant 72 degrees in the building. Now, with winter coming, the building manager has set their thermostat to drop to 66 degrees when no employees are working, to save on energy costs. The fish have shown no ill affects of the cooler water and thankfully, the temperature drop has been very gradual. But, now we'll need to heat the tank. So, I ordered the heaters. The tank is 55 gallons and I felt like two 150 watt heaters placed on opposite sides of the tank would be enough to keep the tank water warmer. Some things you just can't anticipate. But, I'll be more careful and try to think ahead a little more.

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Okay. More on the benefits of large, weekly water changes. I typically remove and replace at least half the tank water in my tanks every week, usually more. When you do this, you don't need complicated filtration and can easily use a sponge filter that costs roughly $10.00. The filter is actually only an aerator and is filtering clean water. By changing so much water, you only need to squeeze out the filters once a month and not even that often. By performing this simple task, you remove most of the toxins that have built up during the week, which isn't much and what few toxins are left in the tank are diluted to a very safe level in all the new, treated tap water. Such a simple way of guaranteeing healthy water conditions for your fish and plants too.

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Here again. Today, we're installing a couple of Eheim "Jager" heaters in a 55 gallon tank we're managing. The heaters are 150 watts a piece and will be positioned next to two large sponge filters. For good heat distribution you should place the heaters on opposite sides of the tank. We chose 150 watt heaters, because we need roughly 5 watts of heat for every gallon of tank water. This way, we provide two larger heaters and neither works too hard to maintain the water temperature. Eheim has an excellent heater and they're priced reasonably at about $25.00 per heater. They're very reliable and are easy to install and set. We keep the temperature at 74 degrees for our fish. Mostly, they're Tetras, but there are some small species of shark and a Pleco.

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Here again. Here's a photo of a 75 gallon tank that has been left to nature. Other than having most of the water removed and replaced weekly, the filter hasn't been cleaned and the bottom hasn't been vacuumed in some time. The lighting is between medium and strong, and we've noticed a different form of algae that's similar to hair algae, but seems to hold onto the aquatic plants like string. The algae is strong stuff and can uproot bottom plants if you try to pull it loose from them. Anyway, it hasn't gotten too bad. But, we may need to remove it by hand.

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Back again. Well, the heaters were installed yesterday. And, wouldn't you know it, one didn't work. After talking up Eheim, one heater was faulty. But, we have a replacement coming. We just need to return the bad heater and replace it. No big deal. We did remove and replace half the tank water and squeezed out the two sponge filters. When you follow an aggressive water change routine, the filtration equipment doesn't do much other than move clean water around the tank. So, expensive water filtering equipment isn't necessary. That can be quite a money saver for whomever owns the tank. When you're paid to maintain a tank for someone else, you'd better make sure they receive their money's worth and then some if you want to keep your job. There's money to be made if you're willing to spend the time to advertise. There are many companies that would love to have a good looking fish tank in their office. We could be a lot busier in this if we wanted to be.

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More info. The 75 gallon tank is a challenge. The type of hair algae that has established itself is obviously feeding on uneaten food in the tank. That's tough to do since I only feed a little every other day. So, the plan is to increase the amount of water we change every week. The larger water change will remove more dissolved food and remove the algae food source. Before long, the algae will die back and we'll have a clear tank again. Of course, the fish won't like the reduction in their food, but that will make them more active. They'll start foraging around the tank more looking for that bit of food that the other fish missed.

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Hello. Just wanted to say "Thanks" to the moderator people for moving me to thread with quite a few fewer posts in it. It's much appreciated. I believe I'm putting out some information that might be helpful and possibly interest someone into putting themselves and their knowledge of fish keeping out to the general public. It's my belief that there are many offices that would love to have a large fish tank as a center piece in their office. I realize there are companies that do this for a living, but their prices are much too high from my experience. Anyway, I'll continue to report on my tanks and what's going on with them. Hopefully, there may be something that can be learned from my keeping so many tanks.

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Here's the continuing story of the faulty Eheim heater. Got a replacement in less than 24 hours and returned the one that was defective. If everything ran that smoothly, boy would the world b e a better place. Well, that's not going to happen. Anyway, installed the heater and have both set for 75 degrees. That's a bit cool for Glo lite Tetras and Tiger Barbs, but there are at least 20 fish in this 55 gallon tank I manage and don't want the fish reproducing, so we keep the water a tiny bit cooler to discourage that sort of thing. The fish are doing very well in spite of their ordeal with the cooler water. Thankfully, the change was so gradual the fish didn't notice it. Any cooler though and they'd be looking for their long underware.


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